In 2015, Apple refused an FBI demand to unlock a shooter’s iPhone following a terrorist attack in California.

The incident sparked a debate over cellphone privacy. Here are four ways law enforcement officials can access the information on your mobile device.

1. With your consent

If you have some kind of involvement with the police, they may ask to search your car, your home or your personal possessions. You may consent to a search of your cellphone. However, you do not have to provide your passcode because under the Fifth Amendment law enforcement cannot force you to give self-incriminating evidence.

2. Warrant to search

Police can search your cellphone if they have a warrant and if your phone is on their list of items to seize. You are not required to answer their questions. Instead, you should ask to speak to your attorney.

3. After your arrest

If law enforcement arrests you, they can remove anything from your person including your cellphone. However, the Supreme Court ruled that officers cannot search the contents without a warrant.

4. Evidence at risk

If the police have reason to believe that the destruction of evidence in an investigation is imminent, they may seize your cellphone without a warrant.

Legal assistance

In the 2015 terrorist attack, professional hackers unlocked the iPhone to give investigators access to the contents. Today a device called GrayKey can open password- and fingerprint-protected devices. Remember that there is legal precedent that governs when law enforcement can search your cellphone and when they cannot. If you have not given your consent for such a search, contact your attorney for guidance on the next steps to take.