middleton033111_04_X17.jpgPippa Middleton could face jail time after a photo was snapped of her and several friends driving around Paris with a semi-automatic handgun pointed at photographers.

The 27-year-old sister-in-law of Prince William rode in the front passenger seat of an Audi convertible as the driver pointed a weapon at the shutterbugs, causing a concerned witness to file a formal complaint with Paris police. If the gun is real, the unidentified man holding it faces up to seven years in prison, and even if the weapon is fake, he'll still face up to two years.

Additionally, a law enforcement source tells Us Magazine, "If the evidence points to [Pippa Middleton's] involvement, she will be prosecuted. Anybody involved in the illegal use of a handgun in public is liable to arrest and interrogation." Yikes!