This article is by Jo Becker, Kirk Johnson and Serge F. Kovaleski.

TUCSON  The police were sent to the home where Jared L. Loughner lived with his family on more than one occasion before the attack here on Saturday that left a congresswoman fighting for her life and six others dead, the Pima County Sheriff’s Department said on Tuesday.

A spokesman, Jason Ogan, said the details of the calls were being reviewed by legal counsel and would be released as soon as the review was complete. He said he did not know what the calls were about  they could possibly have been minor, even trivial matters  or whether they involved Jared Loughner or another member of the household.

A friend of Mr. Loughner’s also said in an interview on Tuesday that Mr. Loughner, 22, was skilled with a gun  as early as high school  and had talked about a philosophy of fostering chaos.

The news of police involvement with the Loughners suggests that county sheriff’s deputies were at least familiar with the family, even if the reason for their visits was unclear as of Tuesday night.