LONDON — In June, as the campaigns to Remain or Leave the European Union were at the final stage, Parliament overwhelmingly approved a bill that critics believe is the most intrusive piece of legislation on mass surveillance in the West.

Just 69 MPs voted against the Investigatory Powers Bill — dubbed the "Snoopers' Charter" by critics — which is now with the House of Lords for further consideration.

Privacy campaigners pointed the finger at measures that would give the government bulk powers to collect citizens' web records, monitor, intercept and even hack smartphones under warrants authorised by ministers.

A recent report by House of Lords peers warned that the charter could endanger journalists and their sources as computer hacking could allow the state to access a journalist's notes or video footage.

It's worth noting that the legislation is the brainchild of Theresa May, the "steely" and "hard-working" Home Secretary who is poised to become the first woman prime minister since Margaret Thatcher.

"Theresa May has unapologetically pushed for expansive and unprecedented surveillance capabilities," Privacy International's Executive Director Gus Hosein told Mashable.

"Now she'll oversee the most important constitutional moment in modern British history. We hope she'll rise to this challenge."

A controversial Home Secretary

May, 59, kept a low profile in the referendum campaign and won the top post after the surprising withdrawal of Andrea Leadsom from the Tory leadership race and David Cameron's resignation announcement.

The daughter of a Church of England's local vicar, May has earned a reputation as a conscientious hard-worker who doesn't spent much time dining and drinking with colleagues.

"The Snoopers' Charter is the most chilling piece of legislation brought forward in a generation"

Over six years as Home Secretary, she didn't shy away from controversy, taking on police corruption and rolling out billboards telling illegal immigrants to "go home or face arrest."

Her uncompromising stance applied also to the Investigatory Powers Bill, which she introduced in November last year following the revelations by the whistleblower Edward Snowden on the scale of mass surveillance carried out by the U.S. National Security Agency (NSA) and Britain's GCHQ.

“As Home Secretary, Theresa May has been among the ministers most outspoken in her distaste for human rights," Bella Sankey, Policy Director For Liberty, told Mashable.

“In recent days she has emphasised her better achievements – reduced stop and search, action to tackle modern slavery and blocking the extradition of Gary McKinnon."

"But while she deserves credit for these actions, May’s ‘Go Home’ Home Office has been deeply divisive and responsible for abject cruelty towards some of the most vulnerable people in our society.

"Her Snoopers’ Charter is the most chilling piece of legislation brought forward in a generation," Sankey said.

At the time, May said the bill would establish "world-leading oversight to govern an investigatory powers regime" which is "more open and transparent than anywhere else in the world."

During the committee stage, the bill was amended to meet privacy concerns raised by MPs and a range of experts and activists over the collection of vast quantities of data in the UK and personal details held in databases.

Privacy concerns

The government's position is that intercepting communications content and metadata was not "mass surveillance" because only a small fraction of these communications would be viewed by a human analyst.

But some organisations, including PI and Liberty, claim the amended version still extends the surveillance powers of agencies in different ways, for example forcing internet providers to retain their customers' data for 12 months.

"This remains a deeply flawed bill, which has changed remarkably little since its draft version was published in November," Harmit Kambo, campaigns director of PI told Mashable in an emailed statement, adding that privacy protections in the bill "begin and end with the inclusion of the word 'Privacy' in a section title."

Among other measures, PI and other organisations claim the bill fails to introduce independent judicial authorisation for surveillance warrants, compels providers to retain customers' data (web browsing history and app use ) for a year and proposes a "request filter" that would allow unauthorised intrusion into personal data.

Perhaps the most worrying aspect, according to privacy campaigners, is that legislation will allow law enforcement and intelligence agencies to carry out IT attacks - known as equipment interference - to acquire data from devices such as mobile phones or computers.

You wouldn't have to be suspected of a crime to be surveilled - the bill allows non-targeted, bulk collection and retention of phone calls, messages, emails and internet browsing history of individuals.

"A wide range of public bodies will have the right to access our private data and communications even if we are not suspected of any crime," Kambo said. "Public bodies should not have this kind of power."

But it closes legal loopholes

May has defended the bill, saying bulk powers had played an important role in every major counter-terrorism investigation over the past decade. She argued spies must be able to hack into foreign computer networks as this was a "a key operational requirement for GCHQ".

The bill will finally close legal loopholes used by the Home Office to bypass Parliament.

Lord Paul Strasburger, a Liberal Democrat peer who sat on the Joint Select Committee that scrutinised the bill, praised its intent to increase transparency "around the powers that the authorities have to intercept our communications and hoover up everyone’s private data."

While criticising the broad powers in the current draft, Strasburger says the bill will finally close legal loopholes used by the Home Office to bypass Parliament to obtain private information.

"The fact that legal loopholes have been used to avoid having to seek Parliament’s approval for very significant intrusions into citizens’ privacy is a disgrace," he wrote.

"The new bill must close all the old loopholes, and the new overly broad powers that are in the current draft of the bill must be eliminated if we are to avoid repeating this scandal of the executive writing its own powers."

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