I am getting the same result no matter which option I click - Rock Paper Scissors JS

Question

As I was working on my "Rock Paper Scissors" game in JavaScript, I am running into an issue. No matter which option I choose, I am always getting the same result (e.g. You Win popup will appear no matter if I choose Rock, Paper, or scissors). I am not getting any error messages. Is there any problem with the "check" function of my code?

Here's my code:

//Variables
let rock = document.getElementById('rock');
let paper = document.getElementById('paper');
let scissors = document.getElementById('scissors');
let choices = [rock, paper, scissors];
let compChoice = Math.random(); 
let userChoice = '';

// Win/lose function
function check () {
    if (userChoice = rock) {
        if (compChoice <= 0.34 /*rock*/) {
            alert('Tie');
        } else if (compChoice > 0.34  && compChoice <= 0.67 /*paper*/) {
            alert ('You Win');
        } else if (compChoice > 0.67 /* scissors */) {
            alert('You Lose');
        }
    } else if (userChoice = paper) {
        if (compChoice <= 0.34 /*rock*/) {
            alert('You Win');
        } else if (compChoice > 0.34  && compChoice <= 0.67 /*paper*/) {
            alert ('Tie');
        } else if (compChoice > 0.67 /* scissors */) {
            alert('You Lose');
        }
    } else if (userChoice = scissors) {
        if (compChoice <= 0.34 /*rock*/) {
            alert('You Win');
        } else if (compChoice > 0.34  && compChoice <= 0.67 /*paper*/) {
            alert ('You Lose');
        } else if (compChoice > 0.67 /* scissors */) {
            alert('Tie');
        }
    }   
}