The lawyer acknowledged the charges on Saturday at Bangkok’s Samranrat Police Station, but denied the both allegations.
Sirikan is accused of conspiring with her clients, the 14 student activists arrested last year for protesting against the National Council for Peace and Order (NCPO), as she allegedly helped them keep personal belongings before their imprisonment on June 26 last year.
Besides the two latest charges, the lawyer had been accused of concealing evidence, obstructing officials from performing their duty, and reporting false information to police in relation to the 14 activists.
Representatives of an EU delegation and other diplomats accompanied Sirikan when she reported to police on Saturday.
Sirikan is the co-founder of Thai Lawyers for Human Rights, an independent body formed after the 2014 coup to provide legal services to people who run afoul of the NCPO.
Its clients include the New Democracy Movement, whose members include the 14 young activists.