The new fees could help recover some of the costs required to fill such a large volume of legal requests, said Al Gidari, a lawyer who for years represented Google and other technology and telecommunications companies. The requests have also grown more complicated as tech companies have acquired more data and law enforcement has become more technologically sophisticated.

“None of the services were designed with exfiltrating data for law enforcement in mind,” said Mr. Gidari, who is now the consulting privacy director at Stanford’s Center for Internet and Society.

Mr. Gidari also said it was good that the fees might result in fewer legal requests to the company. “The actual costs of doing wiretaps and responding to search warrants is high, and when you pass those costs on to the government, it deters from excessive surveillance,” he said.

In April, The Times reported that Google had been inundated with a new type of search warrant request, known as geofence searches. Drawing on an enormous Google database called Sensorvault, they provide law enforcement with the opportunity to find suspects and witnesses using location data gleaned from user devices. Those warrants often result in information on dozens or hundreds of devices, and require more extensive legal review than other requests.

A Google spokesman said that there was no specific reason the fees were announced this month and that they had been under consideration for some time. Reports put out by the company show a rise of just over 50 percent in the number of search warrants received in the first half of 2019 compared with a year earlier. The volume of subpoenas increased about 15 percent. From last January through June, the company received nearly 13,000 subpoenas and over 10,000 search warrants from American law enforcement.

Google will not ask for reimbursement in some cases, including child safety investigations and life-threatening emergencies, the spokesman said.

Law enforcement officials said it was too early to know the impact of the fees, which Google’s notice said would go into effect in mid-January.